3.b Tri-state

Tri-state Buffer Switch Equivalent
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tri-state buffer switch

When activated into its third state it disables or turns “OFF” its output producing an open circuit condition that is neither at a logic “HIGH” or “LOW”, but instead gives an output state of very high impedance, High-Z, or more commonly Hi-Z. Then this type of device has two logic state inputs, “0” or a “1” but can produce three different output states, “0”, “1” or ” Hi-Z ” which is why it is called a “Tri” or “3-state” device.